The proposed research will investigate the extent and manner in which young people with different subtypes of mental subnormality make the transition from childhood to adulthood. We propose to study their socialization, and how it was influenced by their parents, the composition and socio-economic status of their families, and the kinds and quality of service they obtain from the health, education, recreation and other services that are available. To explore these issues we shall ask 22 year old people with different subtypes of mental subnormality about their socialization. We shall ask parents about their experiences with the upbringing of a child who is mentally subnormal. From both parents and children we shall obtain an evaluation of the services provided to help them deal with the special problems of mental subnormality. Subjects of this longitudinal follow-up study will be a defined total population of mentally subnormal people who were identified and studied when they were 8-10 years of age. Detailed research records are available for them and for a comparision sample which will make it possible to determine to what extent the presence of various subtypes of mental subnormality have influenced the socialization process.